Question 12.2

A 62-year-old patient has been admitted to your ICU for routine post-operative monitoring after a vascular surgical procedure.

The pre-operative full blood count (FBC) is displayed below:


Patient Value     

Adult Normal Range


125 g/L*


White Cell Count

7.4 x 109/L



255 x 109/L


Mean Cell Volume

110 fL*


Mean Cell Haemoglobin

30 pg/cell


Mean Cell Haemoglobin Concentration        

320 p/L


12.2.1    List six possible causes for the findings on the FBC.    (3 marks)

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College Answer

Syllabus topic/section:
2.1.21 Applied Pharmacology in Intensive Care.
To allow the candidate to demonstrate competency in data interpretation.
Candidates generally did extremely well in this repeat data question. Candidates are reminded that if the question asks you to list 6 causes there are only marks for 6 answers. If 8 are written the top 6 will be assessed and the bottom 2 causes will not be marked.


This is a repeat of Question 25.2 from the second paper of 2020.

The abnormalities are:

  • A slightly anaemic haemoglobin, for a dude
  • A wildly elevated mean cell volume (i.e. macrocytosis)

The cell haemoglobin content is normal, i.e. this is a macrocytic normochromic anaemia.

There are several common causes:

  • Alcoholism
  • Vitamin B12 deficiency
  • Folate deficiency
  • Myelodysplastic syndromes 

There are also a few uncommon causes:

  • Reticulocytosis
  • Nonalcoholic and alcoholic liver disease
  • Hypothyroidism
  • Multiple myeloma
  • Aplastic anemia
  • Acute leukemia
  • Drugs:
    • trimethoprim, triamterine, nitrous oxide, phenytoin, valproate, chemotherapy agents, HIV antiretrovirals and metformin.


Aslinia, Florence, Joseph J. Mazza, and Steven H. Yale. "Megaloblastic anemia and other causes of macrocytosis." Clinical medicine & research 4.3 (2006): 236-241.

Walker, H. Kenneth, et al. "Peripheral blood smear." (1990). in Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition.